Clip for paralleling packaged integrated circuit chips

ABSTRACT

A clip having two body elements, each containing a plurality of parallel electrical contacts for simultaneously engaging like contact pins of stacked integrated circuit chips in order to electrically connect the contact pins in parallel. At least one of the electrical contacts being deletable from the body element in order to maintain at least one of the contact pins of each of the integrated circuit chips electrically isolated from the others.

BACKGROUND OF THE INVENTION

The present invention is directed to a clip for electrically connectinga plurality of integrated circuit chips in parallel with a similarintegrated circuit chip that is connected in circuit on a circuit board.More particularly the present invention is directed to a clip forstacking dual-in-line integrated circuit packages and for electricallyconnecting the same in parallel so as to increase the density of thecircuit board mounted integrated circuits without the necessity ofextensive redesign.

In designing a microprocessor of the type which utilizes integratedcircuit chips, the designer allocates a fixed amount of board space to afixed number of memory chips, which number depends on the strength ofthe desired processor. Typically, a small microprocessor would utilize asingle memory chip having 1K worth of memory. Once the design isfinalized and the system is in operation, expansion of the memory, to acapability past the design capability, requires expensive modificationsin the circuit boards on which the memory chips are located.

The clip of the present invention enables the paralleling of like memorychips with a memory chip that is mounted to a circuit board. Expansionof memory is generally accomplished by paralleling all common linesexcept, for example, the chip enable (memory enable line), such thatonly the chip receiving an enable signal will be selected and respond tothe signals appearing on the remaining chip pins, for example, the inputand output pins, the address pins, and the data in and the data outpins. It would be highly advantageous to eliminate the redesign of aboard in order to accommodate additional memory chips and, in addition,it would be advantageous to have the capability of adding additionalmemory chips in a manner which enables easy rework of the chips.

SUMMARY OF THE INVENTION

The present invention is directed to a clip for electrically connectingone or more stacked, integrated circuit chips in parallel with a boardmounted integrated circuit chip. The clip is comprised of two bodyelements, each having a plurality of parallel, electrical contactsaffixed thereto, and spaced to correspond to the position of associatedintegrated circuit chip pins. The electrical contacts are exposed over alength which corresponds to the number of integrated circuit chips thatare to be stacked. At least one of the parallel electrical contacts isremovable from a body element in order to eliminate electrical contactto at least one of the integrated circuit chip pins. Additionally, thereis provided a means for urging the two body elements into an engagementso as to provide a secure electrical contact.

According then to the preferred embodiment of the invention, anintegrated circuit chip, such as a memory device, mounted within adual-in-line package, which is affixed to a circuit board, is paralleledwith a number of similar chips by stacking the chips one atop the otherand bending the pins of the chips such that each pin overlaps thecorresponding pin of the chip immediately below it. The clip of thepresent invention is then affixed such that the clip engages all of thepins of the stacked chips. Those pins which are not to be paralleled areplaced in a position which is substantially parallel to the surface ofthe circuit board and an opening, defined by one of the body member,permits the non-paralleled pins to project therethrough. Thenon-parallel pins can then be, connected to chip enabling circuitryeither affixed to the circuit board or to external modules.

From the foregoing, it can be seen that it is a primary object of thepresent invention to provide a clip which facilitates expansion ofmemory capacity for a system;

It is another object of the present invention to provide a means forelectrically paralleling two or more stacked integrated circuit chips;

It is a further object of the present invention to provide a novel meansfor paralleling a plurality of integrated circuit chips, which meanspermits the chips to be quickly separated from each other in order tofacilitate rework;

These and other objects of the present invention will become moreapparent when taken in conjunction with the following description anddrawings, wherein like characters indicate like parts and which drawingsform a part of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a preferred embodiment of the invention;

FIG. 2 is an end view of the clip of the present invention taken alongthe section lines 2--2 in FIG. 1 shown affixing a plurality ofintegrated circuit chips to a circuit board;

FIG. 3 is a sectioned view taken along the section lines 3--3 in FIG. 2;and

FIG. 4 is a perspective view illustrating the overall positioning of theinventive clip of the present application when affixing a number ofintegrated circuit chips in a stacked fashion to a circuit board.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, the clip 10 is shown comprised of a firstand second body member 12A and 12B, respectively. The body member may beformed from an insulating material such as plastic. The body member forthe preferred embodiment is shown to be rectangular in shape, althoughthis shape is in no way limiting. Affixed to the inner surfaces of thefirst and second body members are pivot mounts 18, which pivot mountsare joined by means of a pivotting pin 20. The pivot mounts 18 are of alength which permits the electrical contacts 14 in one body member to besubstantially parallel to the electrical contacts in the other bodymember when the clip is in its operating position. A plurality ofparallel openings 16 extend through each of the body members for alength which corresponds substantially to the total thickness of theintegrated circuit chips that are to be stacked. A plurality of drilledholes 19 extend thru each of the body members along an axis extendingthru the center of each of the plurality of parallel openings 16.Electrical contact pins 14 are pressed thru the openings 19 at allpositions where the integrated circuit pins are to be connected inparallel. A spring 22 is affixed between the body members 12A and 12B tourge the clip into closure at the end having the openings 16.

An integrated circuit chip 28 of the dual-in-line packaged type is shownaffixed to a circuit board 32 by means of its pins 30. A plurality ofsimilar chips 24 are stacked on the board mounted chip 28. Theintegrated circuit chips utilized with the preferred embodiment of thepresent invention were identical memory chips stacked one atop the otherwith their pins 26A overlapping and in electrical contact with like pins30. Those pins which enable individual selection of the chips, such aspins 26B, are positioned horizontally with respect to the circuit board32 and project through the defined opening 16 in the clip body at thelocation wherein the electrical contact 14 is removed. Although only oneelectrical contact pin is shown removed from the clip assembly, it is tobe understood that any number of contact pins may be removed in order topermit the non-paralleling of selected pins of the stacked chips.

Referring now to FIG. 3, wherein the sectioned view of one of the clipbody members is shown. The pins 26A of the integrated circuit chip 24are shown fitting partially into the defined opening 16 of the clip bodymember 12A, while being limited and/or pressed against the electricalcontact pins 14. The one pin labelled 26B is shown extending completelythrough the defined opening 16 so as to permit easy access to the pinfor connection to other enabling electronics and also to maintain thepin in a non-parallel electrical connection.

Referring now to FIG. 4 wherein the clip 10 of the present invention isshown stacking three memory integrated circuit chips 24 onto a boardmounted integrated circuit chip 28. The integrated circuit chip 28 isconnected in circuit onto the board 32. Additional utilization means,not shown, can be connected to the pins 26B for selecting one or more ofthe stacked integrated circuit chips.

Although the invention has been described and illustrated in detail, itis to be clearly understood that the same is by way of illustration andexample only, and is not to be taken by way of limitation, the spiritand scope of the invention being limited only by the terms of theappended claims.

What is claimed is:
 1. A clip for electrically paralleling a stackedplurality of integrated circuit chips each having a number of electricalpins, comprising:a body member adapted to receive said plurality ofintegrated circuit chips; a plurality of electrical contacts associatedwith said body member for connecting a desired number of said electricalpins in parallel; and access openings thru said body member for enablingaccess to those of said electrical pins which are not connected inparallel by said electrical contacts.
 2. A clip according to claim 1 andfurther comprising: means for urging said electrical contacts againstthe electrical pins of said stacked plurality of integrated circuitchips.
 3. A clip for electrically connecting one or more integratedcircuit chips in parallel with a board mounted integrated circuit chipcomprising:two body elements; a plurality of parallel electricalcontacts affixed to each of said body elements and spaced to correspondto the position of associated integrated circuit chip pins, saidelectrical contacts being exposed over a length corresponding to thenumber of integrated circuit chips that are to be paralleled; at leastone of said parallel electrical contacts being removable from said bodyelement in order to eliminate electrical contact to at least one of theintegrated circuit pins; at least one of said body elements has adefined opening along the path of said at least one parallel electricalcontact for permitting the pins of the integrated circuit chips, locatedalong said defined opening to project thru said body member; and meansfor urging said two body elements into engagement.
 4. A clip accordingto claim 3 wherein each of said body members is substantiallyrectangular in shape and has a width that is slightly greater than thelength of the integrated circuit chips.
 5. A clip according to claim 3and further comprising:means for pivotally connecting said two bodyelements at a spaced apart distance which enables positioning each ofsaid parallel electrical contacts into simultaneous engagement with allof the pins of the stacked integrated circuit chips.
 6. A clip forelectrically paralleling a stacked plurality of integrated circuit chipseach having a number of electrical pins, comprising:a body memberadapted to receive said plurality of integrated circuit chips; aplurality of electrical contacts associated with said body member forconnecting a desired number of said electrical pins in parallel; andaccess means associated with said body member for enabling access tothose of said electrical pins which are not to be connected in parallel,wherein said access means is a defined opening along the path of said atleast one electrical contact for permitting the electrical pins of saidstacked plurality of integrated circuit pins positioned along saiddefined opening to project thru said body member.
 7. A clip according toclaim 6 wherein each of said body members is substantially rectangularin shape and has a width that is slightly greater than the length of theintegrated circuit chips.
 8. A clip according to claim 6 and furthercomprising:means for pivotally connecting said two body elements at aspaced apart distance which enables positioning each of said parallelelectrical contacts into simultaneous engagement with all of the pins ofthe stacked integrated circuit chips.
 9. A clip for electricallyconnecting one or more integrated circuit chips in parallel with a boardmounted integrated circuit chip comprising:two body elements; aplurality of parallel electrical contacts affixed to each of said bodyelements and spaced to correspond to the position of associatedintegrated circuit chip pins, said electrical contacts being exposedover a length corresponding to the number of integrated circuit chipsthat are to be paralled; at least one of said parallel electricalcontacts being removable from said body element in order to eliminateelectrical contact to at least one of the integrated circuit pins; meansfor pivotally connecting said two body elements at a spaced apartdistance which enables positioning each of said parallel electricalcontacts into simultaneous engagement with all of the associated pins ofthe stacked integrated circuit chips; and means for urging said two bodyelements into engagement.
 10. A clip for electrically connecting one ormore integrated circuit chips in parallel with a board mountedintegrated circuit chip comprising:two body elements each having aplurality of parallel openings spaced apart a distance corresponding tothe pin spacing of said integrated circuit chips; a plurality ofparallel electrical contacts positioned in said plurality of parallelopenings and being exposed over a length corresponding to the number ofintegrated circuit chips that are to be paralleled; at least one of saidparallel electrical contacts being removable from said body elements inorder to eliminate electrical contact to at least one of the integratedcircuit pins; and means for urging said two body elements intoengagement.